The charges in the federal criminal complaint allege Ali Irsan and his wife falsified documents in order to receive Social Security disability benefits with the assistance of his daughter, Nadia Irsan.

Ali Irsan and his family allegedly secreted assets, such as real estate, vehicles and currency, which would make him and his wife ineligible to receive benefits.

Authorities say Nadia Irsan, who lives with her father and is unemployed, allegedly maintained a bank account with more than $150,000 in cash for her father, which was separate from the benefits received from the SSA. The family also purchased several pieces of real estate and vehicles with cash.

Part of the scam, prosecutors claim, involved putting up mailboxes for homes that didn't exist just so Irsan could claim family members didn't live together. He was then paid more public aid each month.

Irsan's attorney denies the claims.

"I can tell you my experience is there is a lot of times families become estranged and say things that aren't true and that's what we believe is going to come out when we go to trial on this case, John Floyd told Local 2 investigative reporter Jace Larson. "It's my firm belief they are baseless and we look forward to fighting the allegations in open court."

Investigators say Irsan, 56, shot and killed Gelareh Bagherzadeh outside her Galleria-area home on Jan. 15, 2012. She was a graduate student and friends with the suspect's daughter.

A source says Irsan collapsed during a police interview Thursday and was rushed to a Conroe-area hospital, but his condition is not believed to be life-threatening.

Local 2 Investigates has previously reported that investigators believe Irsan also murdered two other people. One of them is Irsan's daughter's husband, Coty Beavers.

Investigators have also looked into a connection between the murder of another daughter's husband in 1999. He has not been charged in either of those two murders.

Local 2 Investigates has been following developments in this case for more than a year. You can read our original stories in the Quick Clicks section above.